Christianity Today has a cover article on Science Fiction. My take is that SF often tries to answer the question of origins by saying aliens seeded our planet, which only delays the question rather than answer it. If life on earth came from another planet, where then did that life come from? Also SF tends to portray aliens either as hostile invaders or benevolent messiahs (Close Encounters is basically a religious movie), or both (To Serve Man). SF can replace trust in Christ with the hope of an ET rescue and/or the godlike evolution of humankind, believing the serpent's lie. CT aptly says that "progress is not our redemption".
aOne positive note: Fox has decided to pick up the next Narnia Movie (the Dawn Treader)!